NONLINEAR ABSORPTION AND REFRACTION IN AN ORGANIC-DYE FUNCTIONALIZED MAIN-CHAIN POLYMER WAVE-GUIDE IN THE 1.5 MU-M WAVELENGTH REGION

We have examined the nonlinear optical properties of a main chain orga nic polymer waveguide in the 1.5 mu m wavelength region. The nonlinear absorption coefficient was estimated to be alpha(2) =0.8-2X10(-11) m/ W in the 1.48-1.61 mu m wavelength range. The wavelength dependence of the nonlinear absorption coefficient suggests that the strong nonline ar absorption originates from two step absorption through overtones of C-H vibrational absorption. The nonlinear refractive index was estima ted to be n(2)=2.8(+/-0.3)X10(-18) m(2)/W at a wavelength of 1.55 mu m . The nonlinear absorption would restrict the applicability of the wav eguide to all-optical switching in this wavelength region. (C) 1995 Am erican Institute of Physics.